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Nature of determination

(p) dynamic system is deterministic if knowing the state of the system at one time means that the system is uniquely specified for all r 6 T. In many cases, the state of a system can be assigned to a set of values with a certain probability distribution, therefore the future behaviour of the system can be determined stochastically. Discrete time, discrete state-space (first order) Markov processes (i.e. Markov chains) are defined by the formula [Pg.18]

Knowing the total history of the process we can extrapolate its future behaviour with the same probability as if we knew only the actual current state. [Pg.18]

The Markovian property of vectorial processes can be lost by reducing the dimensionality of the process. One cannot expect that the knowledge of only a few components is again sufficient to predict the future probability (van Kampen, 1981, p. 80). [Pg.18]

Deterministic dynamic systems generated by autonomous ordinary differential equations. [Pg.18]

In this case we can say that the evolution law does not depend explicitly on the time. Consequently, the time origin can be defined arbitrarily. [Pg.19]


The practical work mentioned in "The Golden Chain of Homer" provides a method of capturing the Universal Seed of Nature, of determining this seed, and growing it to its ultimate perfection using only rainwater. [Pg.50]

Of course, this requires the excess free energy, which is exactly what we are seeking to estimate So this emphasizes the trial-and-error nature of determining a suitable (r ), and may seem a little discouraging. But in fact the result in Eq. (2.15) is most useful, as we now explain ... [Pg.382]

At least eight different kinetic models can be defined, depending on the specification of time (X), state-space (T) and nature of determination (Z). As was explained earlier, time can be discrete (D) or continuous (C), the state-space can be also discrete (D) or continuous (C), and the nature of determination is deterministic (D) or stochastic (S). [Pg.19]

The efficiency and reliability of methods and methodical support of EAC system are dependent on the extent of reliability in the process to sampling and preparing samples. The equipment used for sampling, sample preparation, and determination both in the field and for industrial purposes must work independently in the wide range of temperatures (from -50 to +50 C) and humidity and endure aggressive influence of environment. The ways of sampling are dependent on the phase state of a sample, nature of determined components, and peculiarities of determination methods applied. Generally, it is advisable to... [Pg.44]

When similar atoms are attached to a particular atom, priority order is determined by the nature of the atoms further away. [Pg.356]

In the applications where the compactness of the energy conversion system is the determining factor as in the case of engines, it is important to know the quantity of energy contained in a given volume of the fuel-air mixture to be burned. This information is used to establish the ultimate relations between the nature of the motor fuel and the power developed by the motor it is of prime consideration in the development of fuels for racing cars. [Pg.186]

Simple conventional refining is based essentially on atmospheric distillation. The residue from the distillation constitutes heavy fuel, the quantity and qualities of which are mainly determined by the crude feedstock available without many ways to improve it. Manufacture of products like asphalt and lubricant bases requires supplementary operations, in particular separation operations and is possible only with a relatively narrow selection of crudes (crudes for lube oils, crudes for asphalts). The distillates are not normally directly usable processing must be done to improve them, either mild treatment such as hydrodesulfurization of middle distillates at low pressure, or deep treatment usually with partial conversion such as catalytic reforming. The conventional refinery thereby has rather limited flexibility and makes products the quality of which is closely linked to the nature of the crude oil used. [Pg.484]

An other worst case for the projection technique used is the ease if corrosion is on both sides of the wall in the double wall penetration. Then by the nature of the double wall penetration it is only possible to determine the integral material loss in the penetrating direction without any possibility to distinguish the side on which the erosion can be found. [Pg.567]

In this case, no profound specialised knowledge is required for determination of the type of discontinuities. On the other hand, determination of the nature of damage using a regular flaw detector for manual UT, can be a complicated task for any flaw detection experts, in any case, its solution will require time and qualification of the operator, but. the presence of these conditions will not eliminate the subjective nature of the assessment. [Pg.790]

It is to be noted that not only is the correction quite large, but for a given tip radius it depends on the nature of the liquid. It is thus incorrect to assume that the drop weights for two liquids are in the ratio of the respective surface tensions when the same size tip is used. Finally, correction factors for r/V < 0.3 have been determined, using mercury drops [37],... [Pg.21]

The discussion focuses on two broad aspects of electrical phenomena at interfaces in the first we determine the consequences of the presence of electrical charges at an interface with an electrolyte solution, and in the second we explore the nature of the potential occurring at phase boundaries. Even within these areas, frequent reference will be made to various specialized treatises dealing with such subjects rather than attempting to cover the general literature. One important application, namely, to the treatment of long-range forces between surfaces, is developed in the next chapter. [Pg.169]

Perxanthate ion may also be implicated [59]. Even today, the exact nature of the surface reaction is clouded [59, 79-81], although Gaudin [82] notes that the role of oxygen is very determinative in the chemistry of the mineral-collector interaction. [Pg.477]

A seemingly more stringent test would be to determine whether the ratios of areas for various solids as obtained by means of a given isotherm equation are independent of the nature of the adsorbate. The data summarized in Table XVII-3 were selected from the literature mainly because each author had obtained areas for two or more solids using two or more adsorbates. It is seen... [Pg.630]

As pointed out in Section XVII-8, agreement of a theoretical isotherm equation with data at one temperature is a necessary but quite insufficient test of the validity of the premises on which it was derived. Quite differently based models may yield equations that are experimentally indistinguishable and even algebraically identical. In the multilayer region, it turns out that in a number of cases the isotherm shape is relatively independent of the nature of the solid and that any equation fitting it can be used to obtain essentially the same relative surface areas for different solids, so that consistency of surface area determination does not provide a sensitive criterion either. [Pg.652]

Brunauer (see Refs. 136-138) defended these defects as deliberate approximations needed to obtain a practical two-constant equation. The assumption of a constant heat of adsorption in the first layer represents a balance between the effects of surface heterogeneity and of lateral interaction, and the assumption of a constant instead of a decreasing heat of adsorption for the succeeding layers balances the overestimate of the entropy of adsorption. These comments do help to explain why the model works as well as it does. However, since these approximations are inherent in the treatment, one can see why the BET model does not lend itself readily to any detailed insight into the real physical nature of multilayers. In summary, the BET equation will undoubtedly maintain its usefulness in surface area determinations, and it does provide some physical information about the nature of the adsorbed film, but only at the level of approximation inherent in the model. Mainly, the c value provides an estimate of the first layer heat of adsorption, averaged over the region of fit. [Pg.653]

The existence of a characteristic isotherm (or of a r-plot) gives a very important piece of information about the adsorption potential, at least for polar solids for which the observation holds. The direct implication is that film thickness f, or alternatively n/n is determined by P/I independent of the nature of the adsorbent. We can thus write... [Pg.654]

Studies to determine the nature of intermediate species have been made on a variety of transition metals, and especially on Pt, with emphasis on the Pt(lll) surface. Techniques such as TPD (temperature-programmed desorption), SIMS, NEXAFS (see Table VIII-1) and RAIRS (reflection absorption infrared spectroscopy) have been used, as well as all kinds of isotopic labeling (see Refs. 286 and 289). On Pt(III) the surface is covered with C2H3, ethylidyne, tightly bound to a three-fold hollow site, see Fig. XVIII-25, and Ref. 290. A current mechanism is that of the figure, in which ethylidyne acts as a kind of surface catalyst, allowing surface H atoms to add to a second, perhaps physically adsorbed layer of ethylene this is, in effect, a kind of Eley-Rideal mechanism. [Pg.733]

The physical, chemical cind biological properties of a molecule often depend critically upo the three-dimensional structures, or conformations, that it can adopt. Conformational analysi is the study of the conformations of a molecule and their influence on its properties. Th development of modem conformational analysis is often attributed to D H R Bcirton, wh showed in 1950 that the reactivity of substituted cyclohexanes wcis influenced by th equatoricil or axial nature of the substituents [Beirton 1950]. An equcilly important reaso for the development of conformatiorml analysis at that time Wcis the introduction c analytic il techniques such as infreired spectroscopy, NMR and X-ray crystaillograph] which actucilly enabled the conformation to be determined. [Pg.473]

It must be emphasised that the following substances are merely representative of widely different classes of compounds, and that the test when applied to an unknown compound often provides only a general indication of the probable class to which the compound belongs. Moreoi er, the behaviour of a compound when heated is often determined more by the nature of its substituent groups than by its general character. [Pg.319]

These so-called interaction perturbations Hint are what induces transitions among the various electronic/vibrational/rotational states of a molecule. The one-electron additive nature of Hint plays an important role in determining the kind of transitions that Hint can induce. For example, it causes the most intense electronic transitions to involve excitation of a single electron from one orbital to another (recall the Slater-Condon rules). [Pg.377]

The derivation of these seleetion rules proeeeds as before, with the following additional eonsiderations. The transition dipole moment s itrans eomponents along the lab-fixed axes must be related to its moleeule-fixed eoordinates (that are determined by the nature of the vibrational transition as diseussed above). This transformation, as given in Zare s text, reads as follows ... [Pg.405]

One consequence of the spin-polarized nature of the effective potential in F is that the optimal Isa and IsP spin-orbitals, which are themselves solutions of F ( )i = 8i d >i, do not have identical orbital energies (i.e., 8isa lsP) and are not spatially identical to one another (i.e., (l)isa and (l)isp do not have identical LCAO-MO expansion coefficients). This resultant spin polarization of the orbitals in P gives rise to spin impurities in P. That is, the determinant Isa 1 s P 2sa is not a pure doublet spin eigenfunction although it is an eigenfunction with Ms = 1/2 it contains both S = 1/2 and S = 3/2 components. If the Isa and Is P spin-orbitals were spatially identical, then Isa Is P 2sa would be a pure spin eigenfunction with S = 1/2. [Pg.462]


See other pages where Nature of determination is mentioned: [Pg.109]    [Pg.1617]    [Pg.14]    [Pg.18]    [Pg.147]    [Pg.109]    [Pg.1617]    [Pg.14]    [Pg.18]    [Pg.147]    [Pg.2]    [Pg.143]    [Pg.178]    [Pg.1012]    [Pg.1040]    [Pg.169]    [Pg.542]    [Pg.771]    [Pg.30]    [Pg.35]    [Pg.58]    [Pg.94]    [Pg.326]    [Pg.457]    [Pg.535]    [Pg.536]    [Pg.5]    [Pg.1057]    [Pg.1059]    [Pg.1144]    [Pg.462]    [Pg.97]   
See also in sourсe #XX -- [ Pg.14 , Pg.18 , Pg.19 ]




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